Search results for: new technology in concrete reinforcement
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9944

Search results for: new technology in concrete reinforcement

8924 Recovery of the Demolition and Construction Waste, Casablanca (Morocco)

Authors: Morsli Mourad, Tahiri Mohamed, Samdi Azzeddine

Abstract:

Casablanca is the biggest city in Morocco. It concentrates more than 60% of the economic and industrial activity of the kingdom. Its building and public works (BTP) sector is the leading source of inert waste scattered in open areas. This inert waste is a major challenge for the city of Casablanca, as it is not properly managed, thus causing a significant nuisance for the environment and the health of the population. Hence the vision of our project is to recycle and valorize concrete waste. In this work, we present concrete results in the exploitation of this abundant and permanent deposit. Typical wastes are concrete, clay and concrete bricks, ceramic tiles, marble panels, gypsum, scrap metal, wood . The work performed included: geolocation with a combination of artificial intelligence and Google Earth, estimation of the amount of waste per site, sorting, crushing, grinding, and physicochemical characterization of the samples. Then, we proceeded to the exploitation of the types of substrates to be developed: light cement, coating, and glue for ceramics... The said products were tested and characterized by X-ray fluorescence, specific surface, resistance to bending and crushing, etc. We will present in detail the main results of our research work and also describe the specific properties of each material developed.

Keywords: déchets de démolition et des chantiers de construction, logiciels de combinaison SIG, valorisation de déchets inertes, enduits, ciment leger, casablanca

Procedia PDF Downloads 112
8923 Assessment of Physical and Mechanical Properties of Perlite Mortars with Recycled Cement

Authors: Saca Nastasia, Radu Lidia, Dobre Daniela, Calotă Razvan

Abstract:

In order to achieve the European Union's sustainable and circular economy goals, strategies for reducing raw material consumption, reusing waste, and lowering CO₂ emissions have been developed. In this study, expanded perlite mortars with recycled cement (RC) were obtained and characterized. The recycled cement was obtained from demolition concrete waste. The concrete waste was crushed in a jaw and grinded in a horizontal ball mill to reduce the material's average grain size. Finally, the fine particles were sieved through a 125 µm sieve. The recycled cement was prepared by heating demolition concrete waste at 550°C for 3 hours. At this temperature, the decarbonization does not occur. The utilization of recycled cement can minimize the negative environmental effects of demolished concrete landfills as well as the demand for natural resources used in cement manufacturing. Commercial cement CEM II/A-LL 42.5R was substituted by 10%, 20%, and 30% recycled cement. By substituting reference cement (CEM II/A-LL 42.5R) by RC, a decrease in cement aqueous suspension pH, electrical conductivity, and Ca²⁺ concentration was observed for all measurements (2 hours, 6 hours, 24 hours, 4 days, and 7 days). After 2 hours, pH value was 12.42 for reference and conductivity of 2220 µS/cm and decreased to 12.27, respectively 1570 µS/cm for 30% RC. The concentration of Ca²⁺ estimated by complexometric titration was 20% lower in suspension with 30% RC in comparison to reference for 2 hours. The difference significantly diminishes over time. The mortars have cement: expanded perlite volume ratio of 1:3 and consistency between 140 mm and 200 mm. The density of fresh mortar was about 1400 kg/m3. The density, flexural and compressive strengths, water absorption, and thermal conductivity of hardened mortars were tested. Due to its properties, expanded perlite mortar is a good thermal insulation material.

Keywords: concrete waste, expanded perlite, mortar, recycled cement, thermal conductivity, mechanical strength

Procedia PDF Downloads 89
8922 Studying the Theoretical and Laboratory Design of a Concrete Frame and Optimizing Its Design for Impact and Earthquake Resistance

Authors: Mehrdad Azimzadeh, Seyed Mohammadreza Jabbari, Mohammadreza Hosseinzadeh Alherd

Abstract:

This paper includes experimental results and analytical studies about increasing resistance of single-span reinforced concreted frames against impact factor and their modeling according to optimization methods and optimizing the behavior of these frames under impact loads. During this study, about 30 designs for different frames were modeled and made using specialized software like ANSYS and Sap and their behavior were examined under variable impacts. Then suitable strategies were offered for frames in terms of concrete mixing in order to optimize frame modeling. To reduce the weight of the frames, we had to use fine-grained stones. After designing about eight types of frames for each type of frames, three samples were designed with the aim of controlling the impact strength parameters, and a good shape of the frame was created for the impact resistance, which was a solid frame with muscular legs, and as a bond away from each other as much as possible with a 3 degree gradient in the upper part of the beam.

Keywords: optimization, reinforced concrete, optimization methods, impact load, earthquake

Procedia PDF Downloads 184
8921 Evaluation for Punching Shear Strength of Slab-Column Connections with Ultra High Performance Fiber-Reinforced Concrete Overlay

Authors: H. S. Youm, S. G. Hong

Abstract:

This paper presents the test results on 5 slab-column connection specimens with Ultra High Performance Fiber-Reinforced Concrete (UHPFRC) overlay including 1 control specimen to investigate retrofitting effect of UHPFRC overlay on the punching shear capacity. The test parameters were the thickness of the UHPFRC overlay and the amount of steel re-bars in it. All specimens failed in punching shear mode with abrupt failure aspect. The test results showed that by adding a thin layer of UHPFRC over the Reinforced Concrete (RC) substrates, considerable increases in global punching shear resistance up to 82% and structural rigidity were achieved. Furthermore, based on the cracking patterns the composite systems appeared to be governed by two failure modes: 1) diagonal shear failure in RC section and 2) debonding failure at the interface.

Keywords: punching shear strength, retrofit, slab-column connection, UHPFRC, UHPFRC overlay

Procedia PDF Downloads 258
8920 Smart Airport: Application of Internet of Things for Confronting Airport Challenges

Authors: Ali Safaeianpour, Nima Shamandi

Abstract:

As air traffic expands, many airports have evolved into transit centers for people, information, and commerce, and technology implementation is an absolute part of airport development. Several challenges are in the way of implementing technology in an airport. Airport 4.0 proposes the "Smart Airport" concept, which focuses on using modern technologies such as Big Data, the Internet of Things (IoT), advanced biometric systems, blockchain, and cloud computing to alter and enhance passengers' journeys. Several common IoT concrete topics as partial keys to smart airports are discussed and introduced, ranging from automated check-in systems to exterior tracking processes, with the goal of enlightening more and more insightful ideas and proposals about smart airport solutions. IoT will dramatically alter people's lives by infusing intelligence, boosting the quality of life, and assembling it smarter. This paper reviews the approaches to transforming an airport into a smart airport and describes several enabling components of IoT and challenges that can hinder the implementation of a smart airport's function, which require to be addressed.

Keywords: airport 4.0, digital airport, smart airport, IoT

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8919 Adaption of the Design Thinking Method for Production Planning in the Meat Industry Using Machine Learning Algorithms

Authors: Alica Höpken, Hergen Pargmann

Abstract:

The resource-efficient planning of the complex production planning processes in the meat industry and the reduction of food waste is a permanent challenge. The complexity of the production planning process occurs in every part of the supply chain, from agriculture to the end consumer. It arises from long and uncertain planning phases. Uncertainties such as stochastic yields, fluctuations in demand, and resource variability are part of this process. In the meat industry, waste mainly relates to incorrect storage, technical causes in production, or overproduction. The high amount of food waste along the complex supply chain in the meat industry could not be reduced by simple solutions until now. Therefore, resource-efficient production planning by conventional methods is currently only partially feasible. The realization of intelligent, automated production planning is basically possible through the application of machine learning algorithms, such as those of reinforcement learning. By applying the adapted design thinking method, machine learning methods (especially reinforcement learning algorithms) are used for the complex production planning process in the meat industry. This method represents a concretization to the application area. A resource-efficient production planning process is made available by adapting the design thinking method. In addition, the complex processes can be planned efficiently by using this method, since this standardized approach offers new possibilities in order to challenge the complexity and the high time consumption. It represents a tool to support the efficient production planning in the meat industry. This paper shows an elegant adaption of the design thinking method to apply the reinforcement learning method for a resource-efficient production planning process in the meat industry. Following, the steps that are necessary to introduce machine learning algorithms into the production planning of the food industry are determined. This is achieved based on a case study which is part of the research project ”REIF - Resource Efficient, Economic and Intelligent Food Chain” supported by the German Federal Ministry for Economic Affairs and Climate Action of Germany and the German Aerospace Center. Through this structured approach, significantly better planning results are achieved, which would be too complex or very time consuming using conventional methods.

Keywords: change management, design thinking method, machine learning, meat industry, reinforcement learning, resource-efficient production planning

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8918 Connecting Lives Inside and Outside the Classroom: Why and How to Implement Technology in the Language Learning Classroom

Authors: Geoffrey Sinha

Abstract:

This paper is primarily addressed to teachers who stand on the threshold of bringing technology and new media into their classrooms. Technology and new media, such as smart phones and tablets have changed the face of communication in general and of language teaching more specifically. New media has widespread appeal among young people in particular, so it is in the teacher’s best interests to bring new media into their lessons. It is the author’s firm belief that technology will never replace the teacher, but it is without question that the twenty-first century teacher must employ technology and new media in some form, or run the risk of failure. The level that one chooses to incorporate new media within their class is entirely in their hands.

Keywords: new media, social media, technology, education, language learning

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8917 Experimentation and Analysis of Reinforced Basalt and Carbon Fibres Composite Laminate Mechanical Properties

Authors: Vara Prasad Vemu

Abstract:

The aim of the present work is to investigate the mechanical properties and water absorption capacity of carbon and basalt fibers mixed with matrix epoxy. At present, there is demand for nature friendly products. Basalt reinforced composites developed recently, and these mineral amorphous fibres are a valid alternative to carbon fibres for their lower cost and to glass fibres for their strength. The present paper describes briefly on basalt and carbon fibres (uni-directional) which are used as reinforcement materials for composites. The matrix epoxy (LY 556-HY 951) is taken into account to assess its influence on the evaluated parameters. In order to use reinforced composites for structural applications, it is necessary to perform a mechanical characterization. With this aim experiments like tensile strength, flexural strength, hardness and water absorption are performed. Later the mechanical properties obtained from experiments are compared with ANSYS software results.

Keywords: carbon fibre, basalt fibre, uni-directional, reinforcement, mechanical tests, water absorption test, ANSYS

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8916 Applications of Evolutionary Optimization Methods in Reinforcement Learning

Authors: Rahul Paul, Kedar Nath Das

Abstract:

The paradigm of Reinforcement Learning (RL) has become prominent in training intelligent agents to make decisions in environments that are both dynamic and uncertain. The primary objective of RL is to optimize the policy of an agent in order to maximize the cumulative reward it receives throughout a given period. Nevertheless, the process of optimization presents notable difficulties as a result of the inherent trade-off between exploration and exploitation, the presence of extensive state-action spaces, and the intricate nature of the dynamics involved. Evolutionary Optimization Methods (EOMs) have garnered considerable attention as a supplementary approach to tackle these challenges, providing distinct capabilities for optimizing RL policies and value functions. The ongoing advancement of research in both RL and EOMs presents an opportunity for significant advancements in autonomous decision-making systems. The convergence of these two fields has the potential to have a transformative impact on various domains of artificial intelligence (AI) applications. This article highlights the considerable influence of EOMs in enhancing the capabilities of RL. Taking advantage of evolutionary principles enables RL algorithms to effectively traverse extensive action spaces and discover optimal solutions within intricate environments. Moreover, this paper emphasizes the practical implementations of EOMs in the field of RL, specifically in areas such as robotic control, autonomous systems, inventory problems, and multi-agent scenarios. The article highlights the utilization of EOMs in facilitating RL agents to effectively adapt, evolve, and uncover proficient strategies for complex tasks that may pose challenges for conventional RL approaches.

Keywords: machine learning, reinforcement learning, loss function, optimization techniques, evolutionary optimization methods

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8915 Analytical and Experimental Evaluation of Effects of Nonstructural Brick Walls on Earthquake Response of Reinforced Concrete Structures

Authors: Hasan Husnu Korkmaz, Serra Zerrin Korkmaz

Abstract:

The reinforced concrete (RC) framed structures composed of beams, columns, shear walls and the slabs. The other members are assumed to be nonstructural. Especially the brick infill walls which are used to separate the rooms or spaces are just handled as dead loads. On the other hand, if these infills are constructed within the frame bays, they also have higher shear and compression capacities. It is a well-known fact that, brick infills increase the lateral rigidity of the structure and thought to be a reserve capacity in the design. But, brick infills can create unfavorable failure or damage modes in the earthquake action such as soft story or short columns. The increase in the lateral rigidity also causes an over estimation of natural period of the structure and the corresponding earthquake loads in the design are less than the actual ones. In order to obtain accurate and realistic design results, the infills must be modelled in the structural design and their capacities must be included. Unfortunately, in Turkish Earthquake Code, there is no design methodology for the engineers. In this paper, finite element modelling of infilled reinforced concrete structures are studied. The proposed or used method is compared with the experimental results of a previous study. The effect of infills on the structural response is expressed within the paper.

Keywords: seismic loading, brick infills, finite element analysis, reinforced concrete, earthquake code

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8914 Focusing on the Utilization of Information and Communication Technology for Improving Childrens’ Potentials in Science: Challenges for Sustainable Development in Nigeria

Authors: Osagiede Mercy Afe

Abstract:

After the internet explosion in the 90’s, Technology was immediately integrated into the school system. Technology which symbolizes advancement in human knowledge was seen as a setback by many educators many efforts have been made to help stem this erroneous believes and help educators realize the benefits of technology and ways of implementing it in the classrooms especially in the sciences. This advancement created a constantly expanding gap between the pupil’s perception on the use of technology within the learning atmosphere and the teacher’s perception and limitations hence the focus of this paper is on the need to refocus on the potentials of Science and Technology in enhancing children learning at school especially in science for sustainable development in Nigeria. The paper recommended measures for facilitating the sustenance of science and technology in Nigerian schools so as to enhance the potentials of our children in Science and Technology for a better tomorrow.

Keywords: children, information communication technology (ICT), potentials, sustainable development, science education

Procedia PDF Downloads 488
8913 Seismic Performance of Reinforced Concrete Frame Structure Based on Plastic Rotation

Authors: Kahil Amar, Meziani Faroudja, Khelil Nacim

Abstract:

The principal objective of this study is the evaluation of the seismic performance of reinforced concrete frame structures, taking into account of the behavior laws, reflecting the real behavior of materials, using CASTEM2000 software. A finite element model used is based in modified Takeda model with Timoshenko elements for columns and beams. This model is validated on a Vecchio experimental reinforced concrete (RC) frame model. Then, a study focused on the behavior of a RC frame with three-level and three-story in order to visualize the positioning the plastic hinge (plastic rotation), determined from the curvature distribution along the elements. The results obtained show that the beams of the 1st and 2nd level developed a very large plastic rotations, or these rotations exceed the values corresponding to CP (Collapse prevention with cp qCP = 0.02 rad), against those developed at the 3rd level, are between IO and LS (Immediate occupancy and life Safety with qIO = 0.005 rad and rad qLS = 0.01 respectively), so the beams of first and second levels submit a very significant damage.

Keywords: seismic performance, performance level, pushover analysis, plastic rotation, plastic hinge

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8912 Structural Behavior of Precast Foamed Concrete Sandwich Panel Subjected to Vertical In-Plane Shear Loading

Authors: Y. H. Mugahed Amran, Raizal S. M. Rashid, Farzad Hejazi, Nor Azizi Safiee, A. A. Abang Ali

Abstract:

Experimental and analytical studies were accomplished to examine the structural behavior of precast foamed concrete sandwich panel (PFCSP) under vertical in-plane shear load. PFCSP full-scale specimens with total number of six were developed with varying heights to study an important parameter slenderness ratio (H/t). The production technique of PFCSP and the procedure of test setup were described. The results obtained from the experimental tests were analysed in the context of in-plane shear strength capacity, load-deflection profile, load-strain relationship, slenderness ratio, shear cracking patterns and mode of failure. Analytical study of finite element analysis was implemented and the theoretical calculations of the ultimate in-plane shear strengths using the adopted ACI318 equation for reinforced concrete wall were determined aimed at predicting the in-plane shear strength of PFCSP. The decrease in slenderness ratio from 24 to 14 showed an increase of 26.51% and 21.91% on the ultimate in-plane shear strength capacity as obtained experimentally and in FEA models, respectively. The experimental test results, FEA models data and theoretical calculation values were compared and provided a significant agreement with high degree of accuracy. Therefore, on the basis of the results obtained, PFCSP wall has the potential use as an alternative to the conventional load-bearing wall system.

Keywords: deflection curves, foamed concrete (FC), load-strain relationships, precast foamed concrete sandwich panel (PFCSP), slenderness ratio, vertical in-plane shear strength capacity

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8911 Magnetic Survey for the Delineation of Concrete Pillars in Geotechnical Investigation for Site Characterization

Authors: Nuraddeen Usman, Khiruddin Abdullah, Mohd Nawawi, Amin Khalil Ismail

Abstract:

A magnetic survey is carried out in order to locate the remains of construction items, specifically concrete pillars. The conventional Euler deconvolution technique can perform the task but it requires the use of fixed structural index (SI) and the construction items are made of materials with different shapes which require different SI (unknown). A Euler deconvolution technique that estimate background, horizontal coordinate (xo and yo), depth and structural index (SI) simultaneously is prepared and used for this task. The synthetic model study carried indicated the new methodology can give a good estimate of location and does not depend on magnetic latitude. For field data, both the total magnetic field and gradiometer reading had been collected simultaneously. The computed vertical derivatives and gradiometer readings are compared and they have shown good correlation signifying the effectiveness of the method. The filtering is carried out using automated procedure, analytic signal and other traditional techniques. The clustered depth solutions coincided with the high amplitude/values of analytic signal and these are the possible target positions of the concrete pillars being sought. The targets under investigation are interpreted to be located at the depth between 2.8 to 9.4 meters. More follow up survey is recommended as this mark the preliminary stage of the work.

Keywords: concrete pillar, magnetic survey, geotechnical investigation, Euler Deconvolution

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8910 Structural Evaluation of Airfield Pavement Using Finite Element Analysis Based Methodology

Authors: Richard Ji

Abstract:

Nondestructive deflection testing has been accepted widely as a cost-effective tool for evaluating the structural condition of airfield pavements. Backcalculation of pavement layer moduli can be used to characterize the pavement existing condition in order to compute the load bearing capacity of pavement. This paper presents an improved best-fit backcalculation methodology based on deflection predictions obtained using finite element method (FEM). The best-fit approach is based on minimizing the squared error between falling weight deflectometer (FWD) measured deflections and FEM predicted deflections. Then, concrete elastic modulus and modulus of subgrade reaction were back-calculated using Heavy Weight Deflectometer (HWD) deflections collected at the National Airport Pavement Testing Facility (NAPTF) test site. It is an alternative and more versatile method in considering concrete slab geometry and HWD testing locations compared to methods currently available.

Keywords: nondestructive testing, pavement moduli backcalculation, finite element method, concrete pavements

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8909 Laboratory Evaluation of Asphalt Concrete Prepared with Over Burnt Brick Aggregate Treated by Zycosoil

Authors: D. Sarkar, M. Pal, A. K. Sarkar

Abstract:

Asphaltic concrete for pavement construction in India are produced by using crushed stone, gravels etc. as aggregate. In north-Eastern region of India, there is a scarcity o f stone aggregate. Therefore the road engineers are always in search of an optional material as aggregate which can replace the regularly used material. The purpose of this work was to evaluate the utilization of substandard or marginal aggregates in flexible pavement construction. The investigation was undertaken to evaluate the effects of using lower quality aggregates such as over burnt brick aggregate on the preparation of asphalt concrete for flexible pavements. The scope of this work included a review of available literature and existing data, a laboratory evaluation organized to determine the effects of marginal aggregates and potential techniques to upgrade these substandard materials, and a laboratory evaluation of these upgraded marginal aggregate asphalt mixtures. Over burnt brick aggregates are water susceptible and can leads to moisture damage. Moisture damage is the progressive loss of functionality of the material owing to loss of the adhesion bond between the asphalt binder and the aggregate surface. Hence, zycosoil as an anti striping additive were evaluated in this study. This study summarizes the results of the laboratory evaluation carried out to investigate the properties of asphalt concrete prepared with zycosoil modified over burnt brick aggregate. Marshall specimen were prepared with stone aggregate, zycosoil modified stone aggregate, over burnt brick aggregate and zycosoil modified over burnt brick aggregate. Results show that addition of zycosoil with stone aggregate increased stability by 6% and addition of zycosoil with over burnt brick aggregate increased stability by 30%.

Keywords: asphalt concrete, over burnt brick aggregate, marshall stability, zycosoil

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8908 Optimal Design of Concrete Shells by Modified Particle Community Algorithm Using Spinless Curves

Authors: Reza Abbasi, Ahmad Hamidi Benam

Abstract:

Shell structures have many geometrical variables that modify some of these parameters to improve the mechanical behavior of the shell. On the other hand, the behavior of such structures depends on their geometry rather than on mass. Optimization techniques are useful in finding the geometrical shape of shell structures to improve mechanical behavior, especially to prevent or reduce bending anchors. The overall objective of this research is to optimize the shape of concrete shells using the thickness and height parameters along the reference curve and the overall shape of this curve. To implement the proposed scheme, the geometry of the structure was formulated using nonlinear curves. Shell optimization was performed under equivalent static loading conditions using the modified bird community algorithm. The results of this optimization show that without disrupting the initial design and with slight changes in the shell geometry, the structural behavior is significantly improved.

Keywords: concrete shells, shape optimization, spinless curves, modified particle community algorithm

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8907 Stability of Composite Struts Using the Modified Newmark Method

Authors: Seyed Amin Vakili, Sahar Sadat Vakili, Seyed Ehsan Vakili, Nader Abdoli Yazdi

Abstract:

The aim of this paper is to examine the behavior of elastic stability of reinforced and composite concrete struts with axial loads. The objective of this study is to verify the ability of the Modified Newmark Method to include geometric non-linearity in addition to non-linearity due to cracking, and also to show the advantage of the established method to reconsider an ignored minor parameter in mathematical modeling, such as the effect of the cracking by extra geometric bending moment Ny on cross-section properties. The purpose of this investigation is not to present some new results for the instability of reinforced or composite concrete columns. Therefore, no kinds of non-linearity involved in the problem are considered here. Only as mentioned, it is a part of the verification of the new established method to solve two kinds of non-linearity P- δ effect and cracking together simultaneously. However, the Modified Newmark Method can be used to solve non-linearity of materials and time-dependent behavior of concrete. However, since it is out of the scope of this article, it is not considered.

Keywords: stability, buckling, modified newmark method, reinforced

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8906 Mechanical Properties and Microstructural Analysis of Al6061-Red Mud Composites

Authors: M. Gangadharappa, M. Ravi Kumar, H. N. Reddappa

Abstract:

The mechanical properties and morphological analysis of Al6061-Red mud particulate composites were investigated. The compositions of the composite include a matrix of Al6061 and the red mud particles of 53-75 micron size as reinforcement ranging from 0% to 12% at an interval of 2%. Stir casting technique was used to fabricate Al6061-Red mud composites. Density measurement, estimation of percentage porosity, tensile properties, fracture toughness, hardness value, impact energy, percentage elongation and percentage reduction in area. Further, the microstructures and SEM examinations were investigated to characterize the composites produced. The result shows that a uniform dispersion of the red mud particles along the grain boundaries of the Al6061 alloy. The tensile strength and hardness values increases with the addition of Red mud particles, but there is a slight decrease in the impact energy values, values of percentage elongation and percentage reduction in area as the reinforcement increases. From these results of investigation, we concluded that the red mud, an industrial waste can be used to enhance the properties of Al6061 alloy for engineering applications.

Keywords: Al6061, red mud, tensile strength, hardness and microstructures

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8905 Analysis of the Behavior of the Structure Under Internal Anfo Explosion

Authors: Seung-Min Ko, Seung-Jai Choi, Gun Jung, Jang-Ho Jay Kim

Abstract:

Although extensive explosion-related research has been performed in the past several decades, almost no research has focused on internal blasts. However, internal blast research is needed to understand about the behavior of a containment structure or building under internal blast loading, as in the case of the Chornobyl and Fukushima nuclear accidents. Therefore, the internal blast study concentrated on RC and PSC structures is performed. The test data obtained from reinforced concrete (RC) and prestressed concrete (PSC) tubular structures applied with an internal explosion using ammonium nitrate/fuel oil (ANFO) charge are used to assess their deformation resistance and ultimate failure load based on the structural stiffness change under various charge weight. For the internal blast charge weight, ANFO explosive charge weights of 15.88, 20.41, 22.68 and 24.95 kg were selected for the RC tubular structures, and 22.68, 24.95, 27.22, 29.48, and 31.75 kg were selected for PSC tubular structures, which were detonated at the center of cross section at the mid-span with a standoff distance of 1,000mm to the inner wall surface. Then, the test data were used to predict the internal charge weight required to fail a real scale reinforced concrete containment vessels (RCCV) and prestressed concrete containment vessel (PCCV). Then, the analytical results based on the experimental data were derived using the simple assumptions of the models, and another approach using the stiffness, deformation and explosion weight relationship was used to formulate a general method for analyzing internal blasted tubular structures. A model of the internal explosion of a steel tube was used as an example for validation. The proposed method can be used generically, using factors according to the material characteristics of the target structures. The results of the study are discussed in detail in the paper.

Keywords: internal blast, reinforced concrete, RCCV, PCCV, stiffness, blast safety

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8904 Performance of Staggered Wall Buildings Subjected to Low to Medium Earthquake Loads

Authors: Younghoo Choi, Yong Jun, Jinkoo Kim

Abstract:

In this study seismic performance of typical reinforced concrete staggered wall system structures was evaluated through nonlinear static and incremental dynamic analyses. To this end, and 15-story SWS structures were designed and were analyzed to obtain their nonlinear force-displacement relationships. The analysis results showed that the 5-story SWS structures failed due to yielding of columns and walls located in the lower stories, whereas in the 15-story structures plastic hinges were more widely distributed throughout the stories.

Keywords: staggered wall systems, reinforced concrete, seismic performance

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8903 Patent License of Transfer Technology: Challenges and Opportunities in Indonesia

Authors: Agung Sujatmiko

Abstract:

One of the purposes of patent licensing was to transfer technology from developed countries to developing countries. For this reason, the role of the patent license agreement was very important and had a function as a tool to achieve technological development. This goal was very good, but in fact, many problems and obstacles arose in its implementation, so the technology transfer that had been implemented had not given good results. For this reason, it was necessary to find a solution so that technology could switch properly. The problem approach used the statutory and conceptual approaches. The analysis used was deductive by analyzing general laws and regulations and then concluding. Several regulations related to technology transfer were the main source to find answers to why technology transfer was difficult to achieve and what caused it. Once the cause was known, a solution would be sought.

Keywords: license, patent, technology, tie in clause

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8902 Experimental Assessment of Micromechanical Models for Mechanical Properties of Recycled Short Fiber Composites

Authors: Mohammad S. Rouhi, Magdalena Juntikka

Abstract:

Processing of polymer fiber composites has a remarkable influence on their mechanical performance. These mechanical properties are even more influenced when using recycled reinforcement. Therefore, we place particular attention on the evaluation of micromechanical models to estimate the mechanical properties and compare them against the experimental results of the manufactured composites. For the manufacturing process, an epoxy matrix and carbon fiber production cut-offs as reinforcing material are incorporated using a vacuum infusion process. In addition, continuous textile reinforcement in combination with the epoxy matrix is used as reference material to evaluate the kick-down in mechanical performance of the recycled composite. The experimental results show less degradation of the composite stiffness compared to the strength properties. Observations from the modeling also show the same trend as the error between the theoretical and experimental results is lower for stiffness comparisons than the strength calculations. Yet still, good mechanical performance for specific applications can be expected from these materials.

Keywords: composite recycling, carbon fibers, mechanical properties, micromechanics

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8901 Time-Dependent Behaviour of Reinforced Concrete Beams under Sustained and Repeated Loading

Authors: Sultan Daud, John P. Forth, Nikolaos Nikitas

Abstract:

The current study aims to highlight the loading characteristics impact on the time evolution (focusing particularly on long term effects) of the deformation of realized reinforced concrete beams. Namely the tension stiffening code provisions (i.e. within Eurocode 2) are reviewed with a clear intention to reassess their operational value and predicting capacity. In what follows the experimental programme adopted along with some preliminary findings and numerical modelling attempts are presented. For a range of long slender reinforced concrete simply supported beams (4200 mm) constant static sustained and repeated cyclic loadings were applied mapping the time evolution of deformation. All experiments were carried out at the Heavy Structures Lab of the University of Leeds. During tests the mid-span deflection, creep coefficient and shrinkage strains were monitored for duration of 90 days. The obtained results are set against the values predicted by Eurocode 2 and the tools within an FE commercial package (i.e. Midas FEA) to yield that existing knowledge and practise is at times over-conservative.

Keywords: Eurocode2, midas fea, repeated, sustained loading.

Procedia PDF Downloads 347
8900 Technology Use by African Smallholder Farmers and the Significant Mediating Factors

Authors: Enobong Akpan-Etuk

Abstract:

The willingness of smallholder farmers in Africa to adopt new agricultural technologies has been low, despite the technological advancement in agriculture. Although technology is seen as the main route out of the traditional methods of food production and poverty, the rate of adoption of agricultural technology remains low among farmers in Africa. Factors affecting the adoption of agricultural technologies include the acquisition of information, characteristics of the technology, education of farmers, social capital, farm size, and household size. This paper explored the literature on the influence of the factors that determine the adoption of technology by smallholder farmers.

Keywords: smallholder, technology, adoption

Procedia PDF Downloads 146
8899 Artificial Neural Network Modeling and Genetic Algorithm Based Optimization of Hydraulic Design Related to Seepage under Concrete Gravity Dams on Permeable Soils

Authors: Muqdad Al-Juboori, Bithin Datta

Abstract:

Hydraulic structures such as gravity dams are classified as essential structures, and have the vital role in providing strong and safe water resource management. Three major aspects must be considered to achieve an effective design of such a structure: 1) The building cost, 2) safety, and 3) accurate analysis of seepage characteristics. Due to the complexity and non-linearity relationships of the seepage process, many approximation theories have been developed; however, the application of these theories results in noticeable errors. The analytical solution, which includes the difficult conformal mapping procedure, could be applied for a simple and symmetrical problem only. Therefore, the objectives of this paper are to: 1) develop a surrogate model based on numerical simulated data using SEEPW software to approximately simulate seepage process related to a hydraulic structure, 2) develop and solve a linked simulation-optimization model based on the developed surrogate model to describe the seepage occurring under a concrete gravity dam, in order to obtain optimum and safe design at minimum cost. The result shows that the linked simulation-optimization model provides an efficient and optimum design of concrete gravity dams.

Keywords: artificial neural network, concrete gravity dam, genetic algorithm, seepage analysis

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8898 The Application of Green Technology to Residential Architecture in Hangzhou

Authors: Huiru Chen, Xuran Zhang

Abstract:

At present, the residential architecture in China are still causing high energy consumption and high pollution during their whole life cycle, which can be backward compared with the developed countries. The aim of this paper is to discuss the application of green technology to residential architecture in Hangzhou. This article will start with the development of green buildings, then analyzes the use status of green technology in Hangzhou from several specific measures. Analysis of the typical existing green residential buildings in Hangzhou is an attempt to form a preliminary Hangzhou’s green technology application strategy system. Through research, it has been found that the application of green technology in Hangzhou has changed from putting green to the facade, to the combination of the preservation of the traditional green concept and the modern green technology.

Keywords: application, green technology, Hangzhou, residential architecture

Procedia PDF Downloads 207
8897 Development of the Maturity Sensor Prototype and Method of Its Placement in the Structure

Authors: Yelbek B. Utepov, Assel S. Tulebekova, Alizhan B. Kazkeyev

Abstract:

Maturity sensors are used to determine concrete strength by the non-destructive method. The method of placement of the maturity sensors determines their number required for a certain frame of a monolithic building. Previous studies weakly describe this aspect, giving only logical assumptions. This paper proposes a cheap prototype of an embedded wireless sensor for monitoring concrete structures, as well as an alternative strategy for placing sensors based on the transitional boundaries of the temperature distribution of concrete curing, which were determined by building a heat map of the temperature distribution, where unknown values are calculated by the method of inverse distance weighing. The developed prototype can simultaneously measure temperature and relative humidity over a smartphone-controlled time interval. It implements a maturity method to assess the in-situ strength of concrete, which is considered an alternative to the traditional shock impulse and compression testing method used in Kazakhstan. The prototype was tested in laboratory and field conditions. The tests were aimed at studying the effect of internal and external temperature and relative humidity on concrete's strength gain. Based on an experimentally poured concrete slab with randomly integrated maturity sensors, it was determined that the transition boundaries form elliptical forms. Temperature distribution over the largest diameter of the ellipses was plotted, resulting in correct and inverted parabolas. As a result, the distance between the closest opposite crossing points of the parabolas is accepted as the maximum permissible step for setting the maturity sensors. The proposed placement strategy can be applied to sensors that measure various continuous phenomena such as relative humidity. Prototype testing has also revealed Bluetooth inconvenience due to weak signal and inability to access multiple prototypes simultaneously. For this reason, further prototype upgrades are planned in future work.

Keywords: heat map, placement strategy, temperature and relative humidity, wireless embedded sensor

Procedia PDF Downloads 178
8896 Formulation and Physico-Mechanical Characterization of a Self-Compacting Concrete Containing Seashells as an Addition Material

Authors: Brahim Safi, Mohammed Saidi, A. Benmounah, Jozef Mitterpach

Abstract:

The aim of this work is to study the rheological and physico-mechanical properties of a self-compacting concrete elaborated with sea shells as an addition cementitious (total replacement of limestone fillers) and sand (partial and total substitution fine aggregate). Also, this present study is registered in the context of sustainable development by using this waste type which caused environmental problems. After preparation the crushed shells (obtaining fine aggregate) and finely crushed shells (obtaining end powder), concretes were manufactured using these two products. Rheological characterization tests (fluidity, filling capacity and segregation) and physico-mechanical properties (density and strength) were carried on these concretes. The results obtained show that it can be used as fin addition (by total replacement of limestone) or also used as sand by total substitution of natural sand.

Keywords: seashells, limestone, sand, self-compacting concrete, fluidity, compressive strength, flexural strength

Procedia PDF Downloads 273
8895 Recycling of Plastic Waste into Composites Using Kaolin as Reinforcement

Authors: Gloria P. Manu, Johnson K. Efavi, Abu Yaya, Grace K. Arkorful, Frank Godson

Abstract:

Plastics have been used extensively in both food and water packaging and other applications because of their inherent properties of low bulk densities and inertness as well as its low cost. Waste management of these plastics after usage is troubling in Ghana. One way of addressing the environmental problems associated with these plastic wastes is by recycling into useful products such as composites for energy and construction applications using natural or local materials as reinforcement. In this work, composites have been formed from waste low-density polyethylene (LDPE) and kaolin at temperatures as low as 70 ֯C using low-cost solvents like kerosene. Chemical surface modifications have been employed to improve the interfacial bonding resulting in the enhancement of properties of the composites. Kaolin particles of sizes ≤ 90µm were dispersed in the polyethylene matrix. The content of the LDPE was varied between 10, 20, 30, 40, 50, 60, and 70 %wt. Results obtained indicated that all the composites exhibited impressive compressive and flexural strengths with the 50%wt. composition having the highest strength. The hardness value of the composites increased as the polyethylene composition reduces and that of the kaolin increased. The average density and water of absorption of the composites were 530kg/m³ and 1.3% respectively.

Keywords: polyethylene, recycling, waste, composite, kaolin

Procedia PDF Downloads 173